Working with Phase Modulation in Reaktor

In this tutorial we see how to build a Sine wave oscillator that allows for phase modulation, made entirely from scratch.

In this members only tutorial from the genius mind of salamanderanagram, we get to see a new kind of Sine oscillator being built. This oscillator will allow for phase modulation, which is very similar to frequency modulation and has been used in many popular synths over the years that were commonly believed to be FM synths. It’s a fascinating topic and neat to see the instrument come together one piece at a time. Let’s go ahead and see how it’s done.

First a basic Sine oscillator is built to be used as a comparison test module This way as the designing of the new phase modulation model is built it can be tested against the basic Sine oscillator to make sure it’s all coming together without any issues. This approach does take a lot more power to run, but it also ensures a more successful and accurate design in the end.

The use of the Modulo module is key to making this work. It keeps the signal identical to what was originally being produced by the ramp oscillator earlier in the signal flow, plus the addition of the phase modulation that has been introduced. For those who have not fully understood the function of the Modulo tool in the past, you may want to check out this tutorial from Mike Huckaby trying to break it down into more understandable terms.

Once you have successfully tested the new phase modulation oscillator against the test sine oscillator, you can remove the unnecessary primary sine oscillator. Now the process of making a simple phase modulation synthesizer can begin. Add envelope controls, as well as pitch control and phase modulation control and you are well on your way to creating something that is not found in the Reaktor factory content!